With Sera Snail Collect you can manage snail populations in your aquarium without harmful chemicals. The safe and simple-to-use Sera Snail Collect relies on a basic "bait and trap" principle to capture freshwater aquarium snails. Snails are secured within the trap once they enter the one-way curtain. Spacing between the exterior set of bars can be adjusted according to the particular size of snail you wish to capture. Includes two Sera O-nip Tablets for use as bait. Plastic construction. Light assembly required. The Sera Snail Collect measures 5" x 2-1/2" x 1" high.